/*
silverPDF is sponsored by Aleyant Systems (http://www.aleyant.com)

silverPDF is based on PdfSharp (http://www.pdfsharp.net) and iTextSharp (http://itextsharp.sourceforge.net)

Developers: Ai_boy (aka Oleksii Okhrymenko)

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above information and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR SPONSORS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

*/
#region PDFsharp - A .NET library for processing PDF
//
// Authors:
//   Stefan Lange (mailto:Stefan.Lange@pdfsharp.com)
//
// Copyright (c) 2005-2008 empira Software GmbH, Cologne (Germany)
//
// http://www.pdfsharp.com
// http://sourceforge.net/projects/pdfsharp
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
// DEALINGS IN THE SOFTWARE.
#endregion

using System;
using System.Diagnostics;
using System.Collections;
using System.Globalization;
using System.Text;
using System.IO;
using PdfSharp.Pdf.Internal;
using PdfSharp.Pdf.Content.Objects;
using System.Collections.Generic;

namespace PdfSharp.Pdf.Content
{
  /// <summary>
  /// Represents a writer for generation of PDF streams. 
  /// </summary>
  internal class ContentWriter
  {
    public ContentWriter(Stream contentStream)
    {
      this.stream = contentStream;
#if DEBUG
      //layout = PdfWriterLayout.Verbose;
#endif
    }

    public void Close(bool closeUnderlyingStream)
    {
      if (this.stream != null && closeUnderlyingStream)
      {
        this.stream.Close();
        this.stream = null;
      }
    }

    public void Close()
    {
      Close(true);
    }

    public int Position
    {
      get { return (int)this.stream.Position; }
    }

    //public PdfWriterLayout Layout
    //{
    //  get { return this.layout; }
    //  set { this.layout = value; }
    //}
    //PdfWriterLayout layout;

    //public PdfWriterOptions Options
    //{
    //  get { return this.options; }
    //  set { this.options = value; }
    //}
    //PdfWriterOptions options;

    // -----------------------------------------------------------

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(bool value)
    {
      //WriteSeparator(CharCat.Character);
      //WriteRaw(value ? bool.TrueString : bool.FalseString);
      //this.lastCat = CharCat.Character;
    }

#if old
    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(PdfBoolean value)
    {
      WriteSeparator(CharCat.Character);
      WriteRaw(value.Value ? "true" : "false");
      this.lastCat = CharCat.Character;
    }

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(int value)
    {
      WriteSeparator(CharCat.Character);
      WriteRaw(value.ToString());
      this.lastCat = CharCat.Character;
    }

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(uint value)
    {
      WriteSeparator(CharCat.Character);
      WriteRaw(value.ToString());
      this.lastCat = CharCat.Character;
    }

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(PdfInteger value)
    {
      WriteSeparator(CharCat.Character);
      this.lastCat = CharCat.Character;
      WriteRaw(value.Value.ToString());
    }

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(PdfUInteger value)
    {
      WriteSeparator(CharCat.Character);
      this.lastCat = CharCat.Character;
      WriteRaw(value.Value.ToString());
    }

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(double value)
    {
      WriteSeparator(CharCat.Character);
      WriteRaw(value.ToString("0.###", CultureInfo.InvariantCulture));
      this.lastCat = CharCat.Character;
    }

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(PdfReal value)
    {
      WriteSeparator(CharCat.Character);
      WriteRaw(value.Value.ToString("0.###", CultureInfo.InvariantCulture));
      this.lastCat = CharCat.Character;
    }

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(PdfString value)
    {
      WriteSeparator(CharCat.Delimiter);
#if true
      PdfStringEncoding encoding = (PdfStringEncoding)(value.Flags & PdfStringFlags.EncodingMask);
      string pdf;
      if ((value.Flags & PdfStringFlags.HexLiteral) == 0)
        pdf = PdfEncoders.ToStringLiteral(value.Value, encoding, SecurityHandler);
      else
        pdf = PdfEncoders.ToHexStringLiteral(value.Value, encoding, SecurityHandler);
      WriteRaw(pdf);
#else
      switch (value.Flags & PdfStringFlags.EncodingMask)
      {
        case PdfStringFlags.Undefined:
        case PdfStringFlags.PDFDocEncoding:
          if ((value.Flags & PdfStringFlags.HexLiteral) == 0)
            WriteRaw(PdfEncoders.DocEncode(value.Value, false));
          else
            WriteRaw(PdfEncoders.DocEncodeHex(value.Value, false));
          break;

        case PdfStringFlags.WinAnsiEncoding:
          throw new NotImplementedException("Unexpected encoding: WinAnsiEncoding");

        case PdfStringFlags.Unicode:
          if ((value.Flags & PdfStringFlags.HexLiteral) == 0)
            WriteRaw(PdfEncoders.DocEncode(value.Value, true));
          else
            WriteRaw(PdfEncoders.DocEncodeHex(value.Value, true));
          break;

        case PdfStringFlags.StandardEncoding:
        case PdfStringFlags.MacRomanEncoding:
        case PdfStringFlags.MacExpertEncoding:
        default:
          throw new NotImplementedException("Unexpected encoding");
      }
#endif
      this.lastCat = CharCat.Delimiter;
    }

    /// <summary>
    /// Writes the specified value to the PDF stream.
    /// </summary>
    public void Write(PdfName value)
    {
      WriteSeparator(CharCat.Delimiter, '/');
      string name = value.Value;

      StringBuilder pdf = new StringBuilder("/");
      for (int idx = 1; idx < name.Length; idx++)
      {
        char ch = name[idx];
        Debug.Assert((int)ch < 256);
        if (ch > ' ')
          switch (ch)
          {
            // TODO: is this all?
            case '/':
            case '<':
            case '>':
            case '(':
            case ')':
            case '#':
              break;

            default:
              pdf.Append(name[idx]);
              continue;
          }
        pdf.AppendFormat("#{0:X2}", (int)name[idx]);
      }
      WriteRaw(pdf.ToString());
      this.lastCat = CharCat.Character;
    }

    public void Write(PdfLiteral value)
    {
      WriteSeparator(CharCat.Character);
      WriteRaw(value.Value);
      this.lastCat = CharCat.Character;
    }

    public void Write(PdfRectangle rect)
    {
      WriteSeparator(CharCat.Delimiter, '/');
      WriteRaw(PdfEncoders.Format("[{0:0.###} {1:0.###} {2:0.###} {3:0.###}]", rect.X1, rect.Y1, rect.X2, rect.Y2));
      this.lastCat = CharCat.Delimiter;
    }

    public void Write(PdfReference iref)
    {
      WriteSeparator(CharCat.Character);
      WriteRaw(iref.ToString());
      this.lastCat = CharCat.Character;
    }

    public void WriteDocString(string text, bool unicode)
    {
      WriteSeparator(CharCat.Delimiter);
      //WriteRaw(PdfEncoders.DocEncode(text, unicode));
      byte[] bytes;
      if (!unicode)
        bytes = PdfEncoders.DocEncoding.GetBytes(text);
      else
        bytes = PdfEncoders.UnicodeEncoding.GetBytes(text);
      bytes = PdfEncoders.FormatStringLiteral(bytes, unicode, true, false, this.securityHandler);
      this.Write(bytes);
      this.lastCat = CharCat.Delimiter;
    }

    public void WriteDocString(string text)
    {
      WriteSeparator(CharCat.Delimiter);
      //WriteRaw(PdfEncoders.DocEncode(text, false));
      byte[] bytes = PdfEncoders.DocEncoding.GetBytes(text);
      bytes = PdfEncoders.FormatStringLiteral(bytes, false, false, false, this.securityHandler);
      this.Write(bytes);
      this.lastCat = CharCat.Delimiter;
    }

    public void WriteDocStringHex(string text)
    {
      WriteSeparator(CharCat.Delimiter);
      //WriteRaw(PdfEncoders.DocEncodeHex(text));
      byte[] bytes = PdfEncoders.DocEncoding.GetBytes(text);
      bytes = PdfEncoders.FormatStringLiteral(bytes, false, false, true, this.securityHandler);
      this.stream.Write(bytes, 0, bytes.Length);
      this.lastCat = CharCat.Delimiter;
    }

    /// <summary>
    /// Begins a direct or indirect dictionary or array.
    /// </summary>
    public void WriteBeginObject(PdfObject value)
    {
      bool indirect = value.IsIndirect;
      if (indirect)
      {
        WriteObjectAddress(value);
        if (this.securityHandler != null)
          this.securityHandler.SetHashKey(value.ObjectID);
      }
      this.stack.Add(new StackItem(value));
      if (indirect)
      {
        if (value is PdfArray)
          WriteRaw("[\n");
        else if (value is PdfDictionary)
          WriteRaw("<<\n");
        this.lastCat = CharCat.NewLine;
      }
      else
      {
        if (value is PdfArray)
        {
          WriteSeparator(CharCat.Delimiter);
          WriteRaw('[');
          this.lastCat = CharCat.Delimiter;
        }
        else if (value is PdfDictionary)
        {
          NewLine();
          WriteSeparator(CharCat.Delimiter);
          WriteRaw("<<\n");
          this.lastCat = CharCat.NewLine;
        }
      }
      if (this.layout == PdfWriterLayout.Verbose)
        IncreaseIndent();
    }

    /// <summary>
    /// Ends a direct or indirect dictionary or array.
    /// </summary>
    public void WriteEndObject()
    {
      int count = this.stack.Count;
      Debug.Assert(count > 0, "ContentWriter stack underflow.");

      StackItem stackItem = (StackItem)this.stack[count - 1];
      this.stack.RemoveAt(count - 1);

      PdfObject value = stackItem.Object;
      bool indirect = value.IsIndirect;
      if (this.layout == PdfWriterLayout.Verbose)
        DecreaseIndent();
      if (value is PdfArray)
      {
        if (indirect)
        {
          WriteRaw("\n]\n");
          this.lastCat = CharCat.NewLine;
        }
        else
        {
          WriteRaw("]");
          this.lastCat = CharCat.Delimiter;
        }
      }
      else if (value is PdfDictionary)
      {
        if (indirect)
        {
          if (!stackItem.HasStream)
            if (this.lastCat == CharCat.NewLine)
              WriteRaw(">>\n");
            else
              WriteRaw(" >>\n");
        }
        else
        {
          Debug.Assert(!stackItem.HasStream, "Direct object with stream??");
          WriteSeparator(CharCat.NewLine);
          WriteRaw(">>\n");
          this.lastCat = CharCat.NewLine;
        }
      }
      if (indirect)
      {
        NewLine();
        WriteRaw("endobj\n");
        if (this.layout == PdfWriterLayout.Verbose)
          this.WriteRaw("%--------------------------------------------------------------------------------------------------\n");
      }
    }

    /// <summary>
    /// Writes the stream of the specified dictionary.
    /// </summary>
    public void WriteStream(PdfDictionary value, bool omitStream)
    {
      StackItem stackItem = (StackItem)this.stack[this.stack.Count - 1];
      Debug.Assert(stackItem.Object is PdfDictionary);
      Debug.Assert(stackItem.Object.IsIndirect);
      stackItem.HasStream = true;

      if (this.lastCat == CharCat.NewLine)
        WriteRaw(">>\nstream\n");
      else
        WriteRaw(" >>\nstream\n");

      if (omitStream)
        WriteRaw("  �...stream content omitted...�\n");  // useful for debugging only
      else
      {
        byte[] bytes = value.Stream.Value;
        if (bytes.Length != 0)
        {
          if (this.securityHandler != null)
          {
            bytes = (byte[])bytes.Clone();
            bytes = this.securityHandler.EncryptBytes(bytes);
          }
          Write(bytes);
          if (this.lastCat != CharCat.NewLine)
            WriteRaw('\n');
        }
      }
      WriteRaw("endstream\n");
    }

    public void Write(byte[] bytes)
    {
      if (bytes == null || bytes.Length == 0)
        return;
      this.stream.Write(bytes, 0, bytes.Length);
      this.lastCat = GetCategory((char)bytes[bytes.Length - 1]);
    }

    void WriteObjectAddress(PdfObject value)
    {
      if (this.layout == PdfWriterLayout.Verbose)
        this.WriteRaw(String.Format("{0} {1} obj   % {2}\n",
          value.ObjectID.ObjectNumber, value.ObjectID.GenerationNumber,
          value.GetType().FullName));
      else
        this.WriteRaw(String.Format("{0} {1} obj\n", value.ObjectID.ObjectNumber, value.ObjectID.GenerationNumber));
    }

    public void WriteFileHeader(PdfDocument document)
    {
      StringBuilder header = new StringBuilder("%PDF-");
      int version = document.version;
      header.Append((version / 10).ToString() + "." + (version % 10).ToString() + "\n%\xD3\xF4\xCC\xE1\n");
      WriteRaw(header.ToString());

      if (this.layout == PdfWriterLayout.Verbose)
      {
        this.WriteRaw(String.Format("% PDFsharp Version {0} (verbose mode)\n", VersionInfo.Version));
        // Keep some space for later fix-up.
        this.commentPosition = (int)this.stream.Position + 2;
        this.WriteRaw("%                                                \n");
        this.WriteRaw("%                                                \n");
        this.WriteRaw("%                                                \n");
        this.WriteRaw("%                                                \n");
        this.WriteRaw("%                                                \n");
        this.WriteRaw("%--------------------------------------------------------------------------------------------------\n");
      }
    }
#endif

    public void WriteRaw(string rawString)
    {
      if (rawString == null || rawString.Length == 0)
        return;
      //AppendBlank(rawString[0]);
      byte[] bytes = PdfEncoders.RawEncoding.GetBytes(rawString);
      this.stream.Write(bytes, 0, bytes.Length);
      this.lastCat = GetCategory((char)bytes[bytes.Length - 1]);
    }

    public void WriteLineRaw(string rawString)
    {
      if (rawString == null || rawString.Length == 0)
        return;
      //AppendBlank(rawString[0]);
      byte[] bytes = PdfEncoders.RawEncoding.GetBytes(rawString);
      this.stream.Write(bytes, 0, bytes.Length);
      this.stream.Write(new byte[] { (byte)'\n' }, 0, 1);
      this.lastCat = GetCategory((char)bytes[bytes.Length - 1]);
    }

    public void WriteRaw(char ch)
    {
      Debug.Assert((int)ch < 256, "Raw character greater than 255 dedected.");
      //AppendBlank(ch);
      this.stream.WriteByte((byte)ch);
      this.lastCat = GetCategory(ch);
    }

    /// <summary>
    /// Gets or sets the indentation for a new indentation level.
    /// </summary>
    internal int Indent
    {
      get { return this.indent; }
      set { this.indent = value; }
    }
    protected int indent = 2;
    protected int writeIndent = 0;

    /// <summary>
    /// Increases indent level.
    /// </summary>
    void IncreaseIndent()
    {
      this.writeIndent += indent;
    }

    /// <summary>
    /// Decreases indent level.
    /// </summary>
    void DecreaseIndent()
    {
      this.writeIndent -= indent;
    }

    /// <summary>
    /// Gets an indent string of current indent.
    /// </summary>
    string IndentBlanks
    {
      get { return new string(' ', this.writeIndent); }
    }

    void WriteIndent()
    {
      this.WriteRaw(IndentBlanks);
    }

    void WriteSeparator(CharCat cat, char ch)
    {
      switch (this.lastCat)
      {
        //case CharCat.NewLine:
        //  if (this.layout == PdfWriterLayout.Verbose)
        //    WriteIndent();
        //  break;

        case CharCat.Delimiter:
          break;

        //case CharCat.Character:
        //  if (this.layout == PdfWriterLayout.Verbose)
        //  {
        //    //if (cat == CharCat.Character || ch == '/')
        //    this.stream.WriteByte((byte)' ');
        //  }
        //  else
        //  {
        //    if (cat == CharCat.Character)
        //      this.stream.WriteByte((byte)' ');
        //  }
        //  break;
      }
    }

    void WriteSeparator(CharCat cat)
    {
      WriteSeparator(cat, '\0');
    }

    public void NewLine()
    {
      if (lastCat != CharCat.NewLine)
        WriteRaw('\n');
    }

    CharCat GetCategory(char ch)
    {
      //if (Lexer.IsDelimiter(ch))
      //  return CharCat.Delimiter;
      //if (ch == Chars.LF)
      //  return CharCat.NewLine;
      return CharCat.Character;
    }

    enum CharCat
    {
      NewLine,
      Character,
      Delimiter,
    };
    CharCat lastCat;

    /// <summary>
    /// Gets the underlying stream.
    /// </summary>
    internal Stream Stream
    {
      get { return this.stream; }
    }
    Stream stream;


    class StackItem
    {
      public StackItem(CObject value)
      {
        Object = value;
      }

      public CObject Object;
      //public bool HasStream;
    }

    ArrayList stack = new ArrayList();
  }
}
